The theoretical framework of Sensory Integration Therapy (SIT) was developed in the USA in the 1970s by JEAN AYRES who had studied psychology and neuroscience and was a qualified and practising Occupational Therapist. She saw the need for an approach which would help therapists to assess and treat people with a problem, known as Sensory Integrative Dysfunction (sometimes called Sensory Processing Disorder).
This approach resulted in the development of a treatment model, different from others, that contributed to powerful improvements for people whose neural pathways were assessed as being dysfunctional. The approach became known as Sensory Integration Therapy (SIT). In 2007 Parham et al developed a Fidelity Measure to ensure that those searching for a treatment service reflecting the principles of Ayres’ model could differentiate it from other treatments by searching for Ayres Sensory Integration Therapy or ASI Therapy.